EU Omnibus Package
Major CS3D (CSDDD)
Due Diligence Changes

What Is CS3D (CSDDD)?

The Corporate Sustainability Due Diligence Directive (CS3D) is the EU’s main tool for mandating that companies identify, prevent, mitigate, and, where relevant, remediate adverse human rights and environmental impacts across their operations and value chains.

Unlike purely voluntary sustainability frameworks, CS3D creates legally binding due diligence obligations based on the OECD Due Diligence Guidance for Responsible Business Conduct, focusing on the areas of most severe and most likely harm rather than blanket coverage of every relationship.

Core Due Diligence Steps

Under CS3D, in‑scope companies must embed a structured due diligence process into their policies and management systems, structured around six key steps:

• Integrate due diligence into corporate governance and risk management.
• Identify and assess adverse human rights and environmental impacts in operations and value chains, prioritising areas of highest risk.
• Prevent or minimise actual and potential adverse impacts, deploying corrective measures where needed.
• Monitor and track the implementation and effectiveness of those measures.
• Communicate findings through a public sustainability due diligence statement.
• Provide for or cooperate in remediation when impacts occur.

The Omnibus I reforms make the process more proportionate and risk based, leaning on reasonably available information and reducing the need for blanket style due diligence across every supplier.

How CS3D And CSRD Work Together

CS3D and the Corporate Sustainability Reporting Directive (CSRD) are distinct but complementary. CS3D focuses on operational due diligence, the actions taken to manage impacts, while CSRD focuses on reporting how those impacts are identified, managed and disclosed.

After Omnibus I, a key nuance is that the CS3D level obligation to adopt and implement a climate transition plan has been removed, but CSRD still requires companies to disclose whether they have a climate transition plan and describe its content where material.

Who Must Comply And Why

CS3D now targets the EU’s largest companies, with significantly tightened thresholds:

• EU companies: must have more than 5,000 employees and net worldwide turnover exceeding EUR 1.5 billion.
• EU parent companies of groups meeting the same thresholds on a consolidated basis.
• Non‑EU companies: must generate more than EUR 1.5 billion in turnover within the EU (individually or on a consolidated basis).

This represents a dramatic narrowing compared with the original directive and means CS3D now covers only a small subset of multinationals, while SMEs and smaller players are largely excluded from direct obligations.

Timeline And Applicability

Member States must transpose CS3D into national law by 26 July 2028, with core due diligence obligations (e.g., risk based assessments and mitigation) applying from 26 July 2029.

The annual sustainability due diligence statement must be published from financial years starting on or after 1 January 2030 , aligning notional reporting with the delayed implementation wave.

Key Omnibus I Changes For CS3D

Omnibus I significantly scales back the original CSDDD, while preserving its core logic for the largest firms [web:17][web:52]. Key changes include:

• Narrowed scope: only very large companies remain in scope, excluding SMEs and many mid‑sized EU and non‑EU firms.
• Proportionate due diligence: companies focus deep dive assessments on areas of highest risk, using reasonably available information, and monitor less frequently.
• Climate transition plan removal: the obligation to adopt and implement a climate transition plan has been removed from CS3D; climate planning now sits in the CSRD style disclosure domain.
• Reduced value chain pressure: information requests to business partners are capped, with additional safeguards for partners with fewer than 5,000 employees [web:17][web:40].
• Softer enforcement: civil liability rules are narrowed and largely left to national regimes, with penalties capped at 3% of net worldwide turnover.

Global Reach And Non‑EU Implications

Direct CS3D obligations bite only on very large non‑EU companies that exceed the EUR 1.5 billion EU turnover threshold [web:51][web:55]. Smaller non‑EU companies are not directly in scope but may still face indirect pressure via contracts and ESG data requests from in‑scope EU firms.

In practice, the directive reshapes expectations for global value chains, even for companies that never see the words "CS3D in‑scope" in their own filings.

Benefits And Why It Matters

For affected companies, CS3D rewires risk management from generic ESG narratives to concrete, risk based due diligence. This can improve reputation, reduce liability risk, and strengthen resilience in complex global value chains.

For society, the directive aims to strengthen labour rights and environmental protection across global supply networks, albeit within a more limited and targeted footprint after Omnibus I.

What This Means For Businesses

For companies sitting at or near the new thresholds, the immediate priorities are:

• Re‑assess CS3D status: check whether your employee count and turnover (EU vs worldwide) place you in the revised CS3D scope.
• Map high risk value chain links: build a risk based inventory of operations and partners where human rights and environmental impacts are most likely and most severe.
• Integrate CS3D and CSRD: align due diligence actions (CS3D) with disclosure requirements (CSRD), especially on climate transition planning and value chain monitoring.
• Monitor national implementation: watch how Member States transpose timelines, liability rules, and exemptions, as these will shape day to day obligations from 2028 onward.

Conclusion

The CS3D Omnibus I changes mark a pivotal moment for corporate sustainability due diligence in the EU. While the scope has narrowed significantly, the obligations for those within scope remain substantive and will require careful planning and implementation.

Businesses must evaluate their position relative to the new thresholds and begin preparing proportionate due diligence systems well in advance of the 2028–2030 implementation timeline.

Next Steps For Your Business

For companies directly in scope or at the edge of CS3D thresholds, consider:

• Confirm CS3D status: Analyse headcount and worldwide/EU‑only turnover to see whether Omnibus I thresholds place you in, out of, or near scope.
• Map high risk segments: Identify the parts of your value chain where human rights and environmental risks are most likely and most severe.
• Design risk based due diligence: Implement a scalable process focused on those segments, using reasonably available information and proportionate supplier engagement.
• Align with CSRD: Ensure that CS3D driven assessments and findings inform CSRD style disclosures on value chain impacts, even where climate transition plan obligations have moved from CS3D to CSRD.

Related Articles

• EU CSRD Omnibus Package Major Reporting Changes: How CSRD thresholds, timelines, and ESRS‑related rules changed under Omnibus I.
• Top 10 CSRD Challenges: Where your reporting infrastructure must be strong enough to support CSRD aligned disclosure of CS3D led actions.
• The Role of AI in ESG Data Collection & Analysis: How automation can help manage supplier‑level data, risk flags, and audit‑ready due‑diligence statements.
• Using Blockchain Web3 to Anchor ESG Transparency: How blockchain anchored supplier and impact data integrate with AI to enable verifiable disclosures, eliminating greenwashing.